"Prima facie, the incident appears to be a low-intensity blast. However, the exact cause will be known after reports come from the forensic authorities," the railways maintained.

Madhya Pradesh Home Minister Bhupendra Singh told PTI in Bhopal that "the initial investigation suggests the blast is a terror attack and investigation is underway to unravel the conspiracy behind the incident."

After the blast, the affected coach was segregated from the train and fire extinguishers were used to control the blaze.

According to railways data, 40 incidents, including that of sabotage, have been reported this year as compared to 45 in 2016.

Three incidents are being investigated by the NIA and one by the CBI.

All the passengers of the affected train were taken to Ujjain by another train. After the police clearance, the track has been certified safe for train travel and traffic resumed at 15.12 PM.